1. Field of the Invention
The invention relates to a floating-type clamping device, more particularly to a floating-type clamping device having a safety control unit.
2. Description of the Related Art
Referring to FIG. 1, a conventional floating-type clamping device 1 is used for clamping a plate material (A) to be moved and processed on a worktable (B).
The floating-type clamping device 1 includes a frame body 11, a pipe inlet control valve 12, a pneumatic cylinder unit 13, a floating plate 14, and two grips 15. The floating plate 14 is connected to the frame body 11 and is adapted for disposing the plate material (A) thereon. The grips 15 are connected to the frame body 11 and are adapted to be gripped by an operator. The pneumatic cylinder unit 13 includes two cylinders 131 and a pressing plate 132 connected to the cylinders 131. The pressing plate 132 is operated by the cylinders 131 to move upward and downward. The floating plate 14 cooperates with the pressing plate 132 to clamp the plate material (A) when the pressing plate 132 moves downward.
When the pipe inlet control valve 12 is opened, compressed air is supplied to the cylinders 131 so as to move the pressing plate 132 downward to clamp the plate material (A) between the pressing plate 132 and the floating plate 14. At the same time, the compressed air is supplied to the floating plate 14 and is sprayed from a bottom surface of the floating plate 14 so as to form an air gap between the floating plate 14 and the worktable (B). Therefore, the friction between the floating plate 14 and the worktable (B) can be reduced so as to facilitate the movement of the floating-type clamping device 1 on the worktable (B).
However, if the pipe inlet control valve 12 is opened inadvertently when the plate material (A) is disposed on the floating plate 14 by an operator, the hand of the operator may be injured by the pressing plate 132.
Furthermore, if the operator inadvertently releases the grips 15, the floating-type clamping device 1 may lose balance and move about in an uncontrolled manner, which may cause injury to the operator.
Accordingly, there is a need for a floating-type clamping device with improved safety during operation.